This invention relates to gate roller apparatus and roller units for a slidable gate construction commonly used in conjunction with a fence system for industrial and farm properties.
Large, sliding gates commonly comprising a tubular frame covered with chain-link fencing are often used at a road entrance such as those found at an industrial facility or a large estate, including farm property. These large sliding gates are sometimes referred to as cantilever gates and they are mounted on rollers so that they can readily be moved horizontally to either open or close the gate without undue effort. The gate itself may consist of a long, rectangular framework constructed of tubular metal frames and to this frame work is attached a section of chain-link fencing which may correspond to that used on the fence typically located on both sides of the gate. The tubular horizontal frame members of the gate typically are mounted to ride in or on grooved rollers which are normally mounted on vertical support posts embedded in the ground adjacent the gate opening. It has been recognized that there is a potential safety hazard with cantilevered gates of this type when the rollers that support the sliding gate are exposed. When a gate has exposed rollers, it is possible for an accident to occur if a person using the gate has a finger or piece of clothing caught between one of the rollers and the adjacent horizontal frame member moving in the roller. Accordingly, efforts have been made in the past to make gate systems of this type safer, either by having the roller enclosed in some form of housing or by having the rollers move in and along an enclosed track.
U.S. Pat. No. 5,022,185 issued Jun. 11, 1991 to D. K. Oatman, describes a roller guard for a slidable fence gate having elongate, horizontal frame members of the gate supported on rollers rotatably mounted on horizontal stub shafts. The roller is surrounded by a housing, which includes opposite end walls having inverted U-shaped cavities formed in the bottom end thereof. The horizontal gate frame is able to move through these cavities while at the same time the end walls themselves provide a minimal amount of protection for fingers of a user, tending to keep the fingers away from the periphery of the roller. With this roller guard, it is still possible for there to be a significant gap between the edge of the cavity in each end wall and the horizontal frame of the gate and thus there is still a significant risk of injury with this known roller guard. Another problem with this known system is that the shaft for the roller is supported at only one end and this can create operational and maintenance difficulties for this roller unit, particularly in view of the substantial weight that can be carried by or applied to one of these covered rollers.
A more recent roller guard is that taught in U.S. Pat. No. 5,528,862 which issued Jun. 25, 1996 to Guidance Systems, Inc. This patent specification also teaches a protective roller cover for a sliding gate system, this cover having both a roller enclosure portion with an open bottom and an integral stub shaft and mounting bracket enclosure portion with an open bottom. The sub shaft and closure portion merges with the roller enclosure portion to form a unitary structure. This roller unit can be attached to an adjacent vertical post by means of two U-clamps attached to the roller unit by means of nuts. However, this known system still suffers from some of the deficiencies of the roller guard of U.S. Pat. No. 5,022,185. In particular, it is still possible for fingers to be caught in a gap between the inverted U-shaped recess formed in the end walls of the roller cover and the horizontal gate frame that extends through these recesses.
It is an object of the present invention to provide an improved gate roller apparatus that can be manufactured and sold at a reasonable cost and that provides improved protection for a user""s fingers and/or clothing.
It is a further object of the present invention to provide an improved gate roller apparatus having a roller with a grooved periphery and a hollow guard housing, this housing being fitted with at least one guard member that is movably mounted adjacent at least one end wall of the housing and that helps prevent inadvertent contact of figures (or clothing) with the roller.
According to one aspect of the invention, a gate roller apparatus for a slidable gate system includes a shaft for supporting a roller, a rotatable roller having a grooved periphery mounted on the shaft, and a protective housing substantially surrounding the roller except on one side of the housing which is substantially open. The housing includes a pair of spaced, vertical side walls and at least one end wall extending between and rigidly connecting the side walls. The shaft and roller are mounted in the housing. A mounting mechanism is attachable to the housing for mounting the gate roller apparatus at a suitable fixed location for movably supporting a slidable gate of the slidable gate system. A guard member is mounted on the guard housing adjacent the at least one end wall and has one end adapted to slidingly engage an adjacent side of an elongate guiding frame of the slidable gate during use of the roller apparatus. This guard member helps to prevent a person""s fingers or clothing from entering into the housing and coming into contact with the roller.
In a preferred embodiment, the housing has two of the aforementioned end walls and there is one of the guard members located at each end wall. The preferred guard member is a flat plate member having a U-shaped cavity at one end thereof.
According to another aspect of the invention, a gate roller apparatus for a slidable gate construction includes a shaft for supporting a roller, a rotatable roller having a grooved periphery mounted on the shaft, and a hollow guard housing surrounding the roller from its periphery on one side edge of the roller to a region adjacent edges of the roller on the opposite side edge of the roller. This housing has inner and outer side walls located adjacent opposite side walls of the roller, at least one end wall rigidly secured to adjacent edges of the inner and outer side walls. There is also a guard member mounted on the housing adjacent the at least one end wall and having a cavity formed in one end thereof sized and oriented to receive a portion of an elongate guiding frame of the slidable gate construction. A mounting mechanism is attachable to one side of the housing for mounting the gate roller apparatus at a suitable location for installation of the slidable gate construction. During use of the gate roller apparatus, the guiding frame is able to cooperate with the grooved periphery of the roller in order to have its longitudinal movement guided thereby. The guiding frame is able to extend through the cavity and the guard member is biased so as to slidingly engage an adjacent side of the guiding frame and thereby prevent inadvertent contact of fingers with the grooved periphery of the roller.
The preferred guard housing has two end walls, each of which is rigidly secured to the inner and outer side walls and there is one guard member movably mounted on the housing adjacent each of the two end walls.
According to a further aspect of the invention, a sliding gate system includes a horizontally extending gate having a horizontal gate support bar guided by at least one rotatable, grooved roller mounted on a shaft which in turn is supported on a vertical support post. The improvement in this gate system includes a protective housing substantially surrounding the roller, except on one side of the housing which faces the support bar. This housing includes a pair of spaced-apart vertical side walls and at least one end wall extending between and rigidly connecting the side walls. A mounting mechanism is attachable to the housing for mounting the housing and the shaft to the support post. A guard member is mounted in or on the housing adjacent the at least one end wall and has one end adapted to slidingly engage an adjacent side of the support bar during use of the gate system. The guard member helps to prevent a person""s fingers or clothing from entering into the housing and coming into contact with the roller.
In a preferred embodiment, the guard member has a U-shaped cavity formed in the one end that is adapted to slidingly engage the support bar. This cavity is sized to engage a rounded top portion of the support bar in a close fitting manner.